Arktikpenguin

This would make sense completely, and is exactly what I thought would happen. My car would start about 50% of attempts immediately, or would crank over with no signs of starting ever, and occasionally a large backfire out of the exhaust. Sorry, forgot to mention I'm using S20 Ej205 heads chamber matched to an EJ257. My 02 wrx originally came with an EJ20, but I'm pretty sure EJ205/255/257 all use the same crank pulley up to a point. S20 heads being the USDM EJ205 heads, have no spot for rear mounted cam sensors in the heads. As far as I'm aware, if I wanted to easily use Ej257 sensors for the cams (with B25/V25 Heads) I'd have to modify my harness significantly. Even with B25/V25 heads, I'd have Ej205 cams and cam gears and use the 2.0 Cam sensor as that is what works best.

Hey guys, I just wanted to pick your brain really quickly about an issue and otherwise confusing situation with my triggering on my engine. For context, I own a 2002 Impreza WRX fitted with a built EJ257 utilizing the EJ20 sensors (V7-10 JDM). For around 3000 miles, I drove my car and had 2 minor issues. One was what I believe to be a slight misfire at cruise, and the other was sometimes long cranking/multiple cranks to start the car when it otherwise started just fine on the same map the previous day and would shoot gunshots out of the exhaust. I figured maybe it's my fueling at crank! Recently I found that my tensioner seized, caused the crank to jump 5-6 teeth, and ultimately ended in some Piston to Valve contact. Before I did verify all this, I pulled a triggerscope of the car and noticed it didn't seem muddled, but thought maybe I have a trigger issue. I then stumbled upon a thread of a not so happy camper. Now, I was not thinking this was an issue with my ECU, but likely an issue with the Adjustable Cam Gears I had been provided by Tomioka Racing. After reading the thread below, I noticed that I had the exact same issue as this user. My crank reading was V7-10, my cam reading was V1-6. Wtf? When Tomioka originally released their gears, they had 1998 and older gears, and a claimed 1999+ cam gear set. I jump to their website and find.... in 2023 they now added a separate 2001-2003 Cam Gear with 2 teeth for the trigger, and 1999+ are 7 teeth for the trigger. I have the wrong gears as I ordered my set in mid 2022. I never thought anything of checking the cam gear as 1999+ = 2 teeth (as I incorrectly thought). After reading the thread below, I also see trigger 2 should be set to Reluctor. My car shouldn't even be running well or at all with Trigger 2 set to V7-10 and a Reluctor due to the incorrect cam gear, but it ran fine. I checked my Trigger 2 and found it is set to Optical/Hall and using a Rising Active Edge with a Pull-Up set to ON. I would normally see about 2 trigger errors in a 30 minute drive on Trigger 1, but I cannot log Trigger 2 error counters. My question is, how the heck was my car running decently with the trigger setup for Trigger 2 being so incorrect? Was the ECU potentially ignoring the Cam sensor and just trusting the crank itself at this point (even with timing), or is there something I'm overlooking? The cam gears as far as I know don't even have close to identical spacing for engine timing. FWIW, I have the correct cam gear now so it's not an issue to me.

For what it's worth, I chased grounding issues when I installed my billet RCM TGV Deletes and Corsa Veloce Billet Intake Manifold, even with the grounds going to sanded metal on the intake manifold itself. For the ECU ground (Driver side intake manifold) and Cam/Crank grounds (passenger side intake manifold), I ran those to 10mm bolts on the front side of the cylinder heads. On driver side, this is the dipstick bolt hole. On the passenger side, this sits right between the TGV and Coolant Crossover Pipe outlet to the Radiator. If you need pics, I'd be glad to grab them for you. I have a relocated battery, so I have another ground wire running from the driver head to the ground that the battery normally goes to on the inner fender. I also have the Starter ground and Battery ground from the rear meet up here. On the passenger side, I just have a ground strap running from the cam/crank ground to the passenger inner fender where there is another body ground. To be fair, this may cause interference with cam and crank so I'm considering removing the extra strap here, but I haven't noticed any ill side effects.

Found my issue!! The cobb pulleys "timing mark" is at least 30° off. My eyeball comparison was clearly off, glad we got it sorted out though. If I have any further issues I'll update with a trigger scope. Thank you Adam!!

Left is what is on my engine so that'll be the stock setting triggers then. Looks like I'll have to check my pulley then and grab that scope for you to be sure. My guess is my pulley is wrong, as cobb claims there should be no timing mark

Just to show ya the difference, left is USDM EJ205 Crank sprocket and Driver cam gear, right is JDM EJ205 Crank sprocket and Driver cam gear. Definitely a good difference in both, so if JDM map uses EJ207 crank sprocket it will be the same as USDM EJ205 but cam gears will still be different.

Hey Adam, we checked timing twice to be safe, I also grabbed another oem pulley and a grimmspeed pulley to check vs my pulley and all have the mark in the same spot. I will grab a trigger scope for ya when I get a chance, likely tomorrow morning!!

Hey guys, I'm mostly done with my car but am having issues with what seems to be timing. A thought just popped into my head while driving that seems to make sense of it. We locked timing on my car to 10 BTDC, came with a figure of 32° offset and now it seems to run worse than my car when I put a random 10° offset in to test fire and tune. My car is an 02 USDM WRX. I have a JDM EJ205 in my car that I had to change the intake cam gear and Crank sprocket and sensors over to USDM to properly run it on my USDM ECU. The thought that popped into my head is that the map for the V7 WRX is likely setup for the JDM crank and cam gears plus sensors and would attribute to running better on 10° vs 32° offset. The 32° tune misfires and pre-ignites at idle, the 10° tune does not. I'm using the same idle ignition settings and ignition settings as my carberry tune that does not pop at idle on both tunes to verify. My question is, do you guys happen to have the settings I can use to fix this for USDM before I do some digging? Does my thought process make sense? No ecu fault codes are thrown, but I can grab an oscilloscope if necessary. Thank you guys so much for the support.

Appreciate the info Adam, I went ahead and swapped the active edge to Rising Edge which fixed my temp issue as you said! I also put the YR wire to Ground and turned the pull-up resistor on for the Clutch switch and it works perfectly!! I appreciate your help immensely!!

Hey guys, I've had my ecu for a couple months now and have just been tinkering until warm weather arrives to drive the car and tune it. I've been finishing up wiring in my Continental Flex Fuel Sensor, and a potential clutch switch and just have 3 quick questions. For the Flex Fuel Sensor: For ecu ground and 14v power, I used pins E4 and E5 per the ecu pinout as my TGVs on my USDM vehicle are deleted. My flex fuel sensor shouldn't read properly until after startup and after the lockout time (10s), correct? Ive only cycled my key to on without starting, as my fuel lines aren't connected but noticed my fuel temp reads as 392°F. Also, what settings should I use for the Continental Flex Fuel Sensor? I have the internal pull-up turned on since that seems correct, and active edge is falling. Hoping these are proper. For the Clutch Switch: I've deleted cruise control and could use the upper Cruise Control Switch on the clutch pedal as a DI for Flat Foot Shifting, or so I think? At first I clipped the YG wire and wired that as DI 8, expecting it to ground out upon pressing my clutch pedal to no avail. I tried turning the cruise control button on my dash to on and gave it a shot thinking that could help, still no dice. Am I better off cutting the YR wire to this switch and just running it to a ground to complete this circuit easily as a clutch switch with YG as DI 8 still? My wire colors are taken from the 02 USDM WRX wiring manual, so YG is Yellow-Green and YR is Yellow-Red. Any help is appreciated, I'm just making sure I wire things properly and do it right the first time! Cheers!